When to Plant Dahlias in Uintah County, UT
Dahlias (Dahlia spp.) are the undisputed stars of the late-summer and fall garden, producing an extraordinary range of flower forms — from compact pompons to dinner plate-sized blooms spanning 12 inches — in virtually every color except true blue. Blooming from midsummer until the first hard frost, a single tuber grows into a massive, flower-laden plant that can produce dozens of cut flowers per week. Modern breeding has expanded the palette and forms dramatically; the American Dahlia Society recognizes over 20 flower forms. Extremely rewarding for gardeners willing to invest in the planting, staking, and (in cold zones) annual lifting of tubers.
Uintah County, Utah is in USDA Zone 5b. The average last spring frost is May 10 and the first fall frost is October 4, giving you a growing season of approximately 147 days.
At an elevation of 6,372 feet, Uintah County receives approximately 12.7 inches of rainfall annually with predominantly loam soil. Summer highs average 85°F, providing good warmth for Dahlias during the growing season. With low rainfall, drip irrigation is essential for growing Dahlias successfully. Mulch heavily to conserve soil moisture.
Uintah County Soil Profile
Soil Type
Loam
Soil pH
6.0-7.0
Drainage
Well Drained
Dahlias Planting Timeline — Uintah County, UT
Dahlias Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | April 12 | Apr 12 – Apr 26 |
| Transplant Outdoors | May 17 | May 17 – May 31 |
| Direct Sow | May 17 | May 17 – Jun 7 |
| Bloom | August 9 | Aug 9 – Nov 8 |
Plant 5" deep · 18" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Start Indoors |
| May | Transplant Outdoors Direct Sow |
| June | Direct Sow |
| July | — |
| August | Bloom |
| September | Bloom |
| October | Bloom |
| November | Bloom |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
Moderate — regular watering
📅 Days to Maturity
70–120 days
🧪 Soil pH
Needs 6–7.5 · Your soil: N/A
🗺️ USDA Zone
Zone 5b
📆 Growing Season
147 days in Uintah County
Growing Tips for Uintah County
Plant tubers after all danger of frost has passed and soil temperature reaches 60°F — typically 1–2 weeks after last frost in most zones. Lay tubers horizontally 4–6 inches deep with the eye (growth point) facing up. Do not water until sprouts emerge; wet soil rots dormant tubers. Stake tall varieties (over 3 feet) at planting time to avoid root disturbance later. Pinch growing tips at 12–16 inches to encourage branching and more blooms. Deadhead regularly to extend the blooming season. In zones 8b and warmer, tubers can overwinter in the ground with a layer of mulch. In zones 3–8a, lift tubers after the first killing frost, cure for a week, and store in slightly damp vermiculite or peat at 40–50°F until spring. Divide tubers every year or two; each division must have an eye (bud) to grow.
Companion Planting
Good Companions
Check more plant combinations with our Companion Planting Checker →
Dahlias in Other Locations
Frequently Asked Questions
When should I plant Dahlias in Uintah County, UT?
Uintah County is in Zone 5b with an average last frost of May 10. Plan your Dahlias planting based on this frost date — see the calendar above for exact timing.
What planting zone is Uintah County, UT?
Uintah County, Utah is in USDA Hardiness Zone 5b. The average last spring frost is May 10 and first fall frost is October 4.
Your Uintah County Garden Planner — Free
A 22-page printable planner built for Uintah County (Zone 5b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.